By CBS3 Staff

PHILADELPHIA (CBS) — The Philadelphia teachers’ union calls it a grave threat after a teacher was diagnosed with cancer linked to asbestos. The Philadelphia Federation of Teachers claims the teacher, who works at Meredith Elementary in South Philadelphia, has mesothelioma.

She also worked at nearby George W. Nebinger Elementary, which underwent emergency asbestos abatement last year.

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The union now wants the district to set aside $100 million to clean up asbestos and lead in all city schools.

“I think we want to make sure that we address Meredith immediately, but certainly recognize and understand that there may be other locations that this employee worked at that we’ll need to put together a comprehensive plan and response to,” Philadelphia School District COO Danielle Floyd said. “We stand behind that our buildings are safe for students and staff to come to everyday.”

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The district says 29 schools were cleaned up of environmental hazards this year. Meredith was not one of them, but leaders say a study on issues there will now be accelerated.